FRAME FOR LIQUID GAS BOTTLES AND FILLING METHOD

Abstract

The invention aims to reduce the technical complexity of refilling gas cylinders. To this end, the fitting according to the invention comprises a gas valve for drawing gas and an opening for refilling a liquid gas cylinder. The opening for refilling a liquid gas cylinder can, in particular, be connected so as to conduct the gas, via a valve opening, to a pipe in the fitting in the form of a tube or flexible hose. This pipe can penetrate at least 300 mm, preferably at least 400 mm, into a liquid gas cylinder when the fitting is connected to the cylinder. As a result, the pipe can penetrate the liquefied portion of the gas, which primarily allows for very rapid emptying by pumping. Emptying is necessary when a refilled gas cylinder is found to be leaky. This provides an advantage in terms of speed.In principle, an opening is provided on the underside of the fitting adjacent to the tube or flexible hose. The underside is the side adjacent to the liquid gas cylinder or located entirely within the cylinder or the neck of the cylinder when the fitting is connected to a liquid gas cylinder. This opening on the underside can be connected to the gas valve to conduct the gas, generally by rotating a suitable handle. The tube or flexible hose extends beyond this opening, preferably by at least 200 mm, and more preferably by at least 300 mm. The invention also relates to a method for refilling a liquid gas cylinder using this fitting.

Description

[0001] The invention relates to a fitting for liquefied gas cylinders and a method for refilling with liquefied gas.

[0002] A gas cylinder is a pressure vessel, usually made of metal, typically steel, used for transporting and storing pressurized gases. Such a cylinder can have a volume of more than 100 liters. The nominal pressure can reach several hundred bar.

[0003] Liquefied petroleum gas (LPG) cylinders contain gases such as LPG in liquefied form. Common gases include ethane, propane, butane, and mixtures thereof. These gases can be liquefied at room temperature under relatively low pressure. The liquefied petroleum gas content of such cylinders typically ranges from 3 to 33 kg. The height of these cylinders is usually between 420 mm and 1290 mm, and the cylinder diameter is typically between 200 mm and 318 mm.

[0004] Liquefied petroleum gas (LPG) cylinders are sealed with a fitting to which a suitable hose can be screwed, usually in conjunction with a pressure regulator, for the controlled withdrawal of their contents. Furthermore, the dispensing fitting of LPG cylinders contains a safety valve that limits the permissible overpressure in the cylinder to, for example, approximately 30 bar to prevent bursting.

[0005] Typically, the fitting of such a liquid gas cylinder has a side-mounted connection that serves as a gas valve, used for both filling and dispensing. Lines are manually screwed onto this gas valve for both dispensing and refilling. When the gas valve is open, the side-mounted connection is connected to an opening on the underside of the fitting, allowing gas to flow. This underside, with its opening, is located above the liquid level when the liquid gas cylinder is upright. Therefore, when gas is dispensed, only the gas that is in a gaseous state above the liquid level is drawn off.

[0006] Liquefied petroleum gas (LPG) cylinders are used to operate gas stoves, gas cookers, gas grills, gas heaters, or gas patio heaters. Once an LPG cylinder is empty, the consumer returns it to the point of sale for refilling. After being returned, the cylinder is transported from the point of sale to a central filling plant or station.

[0007] To facilitate refilling, it is known from publication DE 43 34 182 A1 to provide a central filling point in addition to a side connection nozzle or side gas valve. Filling can then be carried out from above without the need to align a laterally protruding gas valve.

[0008] Document FR 55 136 E describes a fitting for a liquid gas cylinder with a gas tap for gas withdrawal and an opening for refilling the cylinder. On the underside of the fitting is a pipe that extends approximately to the bottom of the liquid gas cylinder and protrudes from an adjacent, parallel pipe.

[0009] The purpose of the invention is to reduce the technical effort required for refilling gas cylinders.

[0010] The object of the invention is achieved by a fitting with the features of the main claim. Advantageous embodiments are described in the dependent claims. An advantageous method for refilling comprises the features of the dependent claim.

[0011] To solve the problem, a fitting according to the claim comprises a gas tap for gas withdrawal and an opening for refilling a liquid gas cylinder. The refilling opening can be connected to a hose-like or tubular line of the fitting, extending at least 300 mm, preferably at least 400 mm, into the liquid gas cylinder when the fitting is connected to such a cylinder, particularly by opening a valve. This allows the line to extend into the liquefied part of the gas, enabling very rapid emptying by pumping. Emptying is necessary if a refilled gas cylinder proves to be leaking. This results in a speed advantage.

[0012] There is an opening on the underside of the fitting adjacent to the tubular or pipe. The underside is the side that abuts the liquefied gas cylinder or is located entirely within the cylinder or cylinder neck when the fitting is connected to a liquefied gas cylinder. This opening on the underside can be connected to the gas valve, usually by turning a corresponding handle. The tubular or pipe projects from this opening, preferably by at least 200 mm, and more preferably by at least 300 mm.

[0013] This ensures that gas can be drawn from above the liquid level via the gas tap and is therefore immediately available in the form in which the gas is needed in case of consumption.

[0014] The hose-like or tubular line is therefore preferably long enough to reach the bottom of a gas cylinder connected to the fitting. As a rule, this line is therefore no longer than 1290 mm.

[0015] The refill opening for the LPG cylinder is located on the top of the fitting. This simplifies refilling, as the LPG cylinder does not need to be repositioned for refilling. In particular, this allows for automated refilling in an automated filling station with minimal technical effort.

[0016] The gas tap, through which the gas is drawn for consumption, is preferably positioned to the side of the fitting. The gas tap can be opened and closed by means of a rotary handle or handwheel. The handwheel is advantageously arranged around the refilling inlet. The handwheel operates, for example, a nut with a spindle, such that a designated component can be moved up and down. This opens or closes the gas tap.

[0017] In one design, the refilling opening of a liquid gas cylinder can be opened and closed by a valve. This facilitates and speeds up refilling, as liquid pressure alone may be sufficient to open the valve.

[0018] The valve preferably comprises a valve body that is pressed into its closed position by a pre-tensioned spring. This allows the valve to be opened for refilling solely by liquid pressure. Furthermore, emptying by pumping is facilitated, as the valve can be opened by connecting a nozzle or the pin of a suction head to the designated opening. Suction can then commence immediately, enabling automated refilling, which can even be performed by an end user, taking into account the necessary increased safety precautions.

[0019] The valve body is preferably a hollow cylinder comprising lateral openings. The valve body can then advantageously be part of the line through which liquid gas is fed into the bottle for refilling or through which liquid gas is extracted for emptying.

[0020] The valve body is preferably provided with a circumferential, replaceable sealing ring that seals the valve liquid- and gas-tight when closed. In the event of a leak, replacing the sealing ring is usually sufficient to restore the valve's functionality.

[0021] In an advantageous embodiment, the sealing ring is pressed against a conical transition when the valve is closed. This transition connects a tubular section to a tubular section that is wider than the first. This design allows the two tubular sections to be used as inlet pipes, enabling a compact design with minimal technical effort.

[0022] In one embodiment, a closing element, particularly in the form of a hollow cylindrical section, is provided which interrupts a gas-conducting connection between the gas valve and the opening on the underside of the fitting, into which gas from a connected liquefied gas cylinder can flow, when the valve body is moved to its open position. This ensures that, in the case of emptying by pumping, liquid is pumped out and not gas, which would delay the emptying process.

[0023] The hollow cylindrical section is preferably a section of the pipe that connects the gas valve to an opening on the underside of the fitting, into which gas from a connected liquefied gas cylinder can flow. This reduces the technical effort of manufacturing and also enables a compact design.

[0024] The opening for refilling a liquid gas cylinder is preferably funnel-shaped to facilitate connection with a filling head or suction head by centering.

[0025] The fitting is advantageously designed so that gas can either be drawn off via the gas tap or refilled or emptied via the designated opening. It is therefore not possible to refill and draw off gas via the gas tap simultaneously. This avoids risks during gas withdrawal or refilling.

[0026] In one embodiment of the invention, an additional gas extraction option is provided, preferably via a quick-release coupling. A hose, for example, can be connected to this additional gas extraction option for continuous, non-adjustable gas extraction. This additional gas extraction option is intended for balloonists to ensure a continuous gas supply to a flame. This flame serves, for example, as a pilot light. This flame generally requires only a small amount of gas. This prevents, for example, excessive gas consumption by turning the pilot light control knob too far. If a quick-release coupling is provided, gas extraction can only be enabled by connecting a corresponding coupling. This prevents accidental opening.

[0027] In one design, there is a burst protection device that is destroyed in the event of excessively high internal pressure, in order to allow gas to escape in a controlled manner and thus reduce excessively high internal pressure.

[0028] The invention is explained in more detail below using figures.

[0029] They show: Figure 1: Fitting with closed gas tap and closed valve; Figure 2: Fitting with closed gas tap and open valve; Figure 3: Fitting with closed gas tap and open valve; Figure 4: Fitting with open gas tap and closed valve; Figure 5: Fitting in a three-dimensional representation.

[0030] The Figure 1Figure 1 shows a sectional view of a fitting 1 for a gas cylinder. A gas tap 2 with an external thread protrudes laterally, horizontally from a stationary gas cylinder (not shown) when the fitting 1 is connected to a gas cylinder as intended. The line of a gas appliance, such as a gas grill, can be screwed onto the gas tap 2 to draw gas.

[0031] In addition to the laterally projecting nozzle 2, there is a funnel-shaped opening 3 on the top of the fitting 1. This upward-facing funnel-shaped opening 3 serves as the central filling and extraction point. For filling or extraction, the funnel-shaped inlet or opening 3 is connected to a filling or extraction head of a gas filling station.

[0032] An externally accessible upper area of ​​the outer wall of the central filling point has two circumferential grooves 4 to enable a positive-locking grip with complementary shaped grippers of a filling or extraction head. This creates a positive-locking connection between the outer wall with the grooves 4 and an extraction or filling head during filling or extraction of gas, preventing unplanned detachment of a head during the filling or emptying of a gas cylinder.

[0033] To ensure a tight seal during filling or emptying, a sealing ring 5 is held in the funnel-shaped opening 3 by a corresponding circumferential groove. A filling head or suction head is pressed against this sealing ring 5 during filling or emptying.

[0034] A hollow cylindrical valve body 6 has a sealing ring 7 in its lower region, which is held in a corresponding circumferential groove of the valve body 6. A spring 8 biases the valve body 6 towards the opening 4. This presses the sealing ring 7 against a conical transition 9 to close the valve. Access via the opening 4 into the fitting 1 is then, as shown in the Figure 1 The valve is shown to be gas-tight and liquid-tight, and more reliably and permanently sealed compared to the ball valve of the central filling point known from publication DE 43 34 182 A1. In the event of a leak in the valve due to fatigue, it is usually sufficient to replace only the sealing ring 9.

[0035] The valve body 6 is located in the closed state of the valve as shown in the Figure 1shown predominantly in a tubular section 10, the inner diameter of which corresponds to the outer diameter of the valve body 6. The valve body 6 is therefore guided through this tubular section 10.

[0036] The spring 8 is located within a tubular section 10 that is wider than the spring 8. The tubular section 10 is connected by the conical transition 9 to a tubular section 11 that is also wider. The inner diameter of the wider section 11 is slightly larger than the diameter of the spring 8. The wider section 11 therefore serves, among other things, to hold and guide the spring 8 when it is further compressed to open the valve.

[0037] The hollow cylindrical valve body 6 is closed at its lower end by a rod 12. The rod 12 extends into a cylinder 13. The inner diameter of the cylinder 13 is larger than the outer diameter of the rod 12, leaving a clearance 14 between the cylinder 13 and the rod 12.

[0038] The end of the hollow cylindrical valve body 6 opposite the rod 12 is open. Furthermore, the valve body 6 has lateral openings 15 near the rod 12, which are connected to or lead into its interior via gas passages. If the valve body 6 is pressed downwards by liquid pressure or mechanically until the lateral openings 15 enter the widened section 11, the valve is open. The open state of the valve is indicated by the Figure 2 and 3 .

[0039] To open and close the side port 2, there is a rotary handle 16, also called a handwheel. By turning the rotary handle or handwheel 16 accordingly, the cylinder 13 can be moved back and forth between a closed position and an open position. Figure 1 Figure 1 shows the closed position of cylinder 13. A sealing ring 17 at the lower end of cylinder 13 is then pressed against a ramp 18 to lock it. This lock is released by moving the cylinder upwards by turning the rotary handle 16 accordingly. Figure 4 shows the open position of cylinder 13.

[0040] Cylinder 13 is sealed against a section 21 of the housing wall of the fitting 1 by sealing rings 19. Furthermore, cylinder 13 is sealed against a cylindrical lower section 22 of the rotary handle 16 by sealing rings 20. The sealing rings 19 and 20 prevent gas from escaping the fitting.

[0041] The rotary handle 16 is rotatably held by a ball bearing 23. A cap 24 is screwed onto the housing section 21 to rotatably connect the rotary handle 16 to the housing section 21.

[0042] The fitting 1 has two openings 25 and 26 on its underside (see in particular also the three-dimensional representation of the Figure 5 ). This underside is located inside the gas cylinder or in the cylinder neck when the fitting is connected to a gas cylinder as intended.

[0043] The opening 25 is located at the lower end of a hose-like or tube-shaped line 27 at the base of a correspondingly connected gas cylinder. Through this opening 25, the gas cylinder is filled with gas or liquefied gas is extracted after the valve with the valve body 6 is opened. Gas is drawn from the cylinder for consumption by a device connected to the gas tap 2 through the other opening 26, after the gas tap has been opened by turning the rotary handle 16.

[0044] The opening 26 is connected to an inner opening 28 via a gas conductor.

[0045] A hollow cylindrical section 29 is connected to the lower end of the rod 12 and has an opening 30 in the transition area between the rod 12 and the section 29. When the valve body 6 is pressed downwards, the hollow cylindrical section 29 is pressed against a sealing ring 31 located at the lower end of a guide 32.

[0046] The Figure 1 This shows the case where fitting 1 is closed. Suction or filling is not possible because the valve is closed. Gas withdrawal via gas tap 2 is not possible because this is prevented by pressing the sealing ring 17 against the inclined surface 18, thus closing the gas tap.

[0047] The Figure 2This illustrates filling via fitting 1. The side port 2 is closed, and the funnel-shaped opening 4 is connected to a filling head (not shown) which is pressed against the sealing ring 5 in the funnel-shaped opening 3 to create a liquid-tight seal. This ensures that the liquid in the Figure 1The opening 28 shown is closed. A gas-conducting connection between the gas valve and the opening 26 located on the underside is thus interrupted. Liquefied gas is now pumped into the funnel-shaped opening 3 in the direction of arrow 33. This pushes the valve body 6 downwards until the hollow cylindrical section 29 is pressed against the sealing ring 31. The lateral openings 15 of the valve body 6 are now located within the widened tubular section 11. The liquefied gas pumped in along arrow 33 can now escape from the openings 15 of the valve body 6 into the widened tubular section 11. Within the widened tubular section 11, the liquefied gas can flow around the lower section of the valve body 6, as illustrated by arrows 34.From the widened tubular section 11, the liquefied gas flows into the space 14 between rod 12 and housing section 21 and thus enters the tubular or hose-like line 27 as shown by arrows 35 and 36. At the lower end of the tubular or hose-like line 27, the liquefied gas then exits the fitting 1 as shown by arrow 37 and thus reaches the bottom of a gas cylinder (not shown) to which the fitting 1 is attached.

[0048] The Figure 2 illustrates that the hollow cylindrical section 29 has a smaller outer diameter 38 in an upper region, in order to thus, in the case of the Figure 2 to create such a distance to the adjacent inner wall of the housing that a gas flow in the direction of arrow 36 is possible.

[0049] For extraction or emptying, the valve body 6 is mechanically pressed downwards by a pin or nozzle of an extraction head mounted on the funnel 3. Liquid gas can then be extracted in accordance with arrows 39 to 43, as shown in the Figure 3 As shown, since the hose or pipe 27 draws gas from the bottom, this ensures that only liquefied gas is extracted and no gaseous atmosphere is present above the liquid level in the gas cylinder. A liquid gas cylinder can therefore be emptied particularly quickly and with minimal effort.

[0050] The Figure 4Figure 1 shows the fitting 1 in the open position of the gas tap 2 and in the closed position of the valve. The gas tap 2 is open because the valve body 6 is in its closed position and the cylinder 13 has been moved upwards by rotating the section 16, thus removing the sealing ring 17 from the inclined surface 18. The gas, which is located above the liquid level in the liquefied gas cylinder, can now enter the opening 26 according to arrow 44 and flow to the inner opening 28. From the opening 28, the gas passes into the interior of the hollow cylindrical section 29 according to arrow 45. The gas then exits through the opening 30 at the upper end of the hollow cylindrical section 29 and enters the space 14 according to arrow 46.Since there is now a gap between the sealing ring 17 and the slope 18, the gas can flow further into the nozzle of the gas tap 2 according to the arrow 47 and from there be directed to the consumer according to the arrow 48.

[0051] In a suitable embodiment of such a fitting, it is particularly advantageous to achieve that either gas can be withdrawn via the gas tap or refilling or emptying can take place via the central opening 3. It is then not possible to refill and withdraw gas via the gas tap simultaneously.

[0052] The refilling procedure also includes emptying in case a gas leak is detected. Emptying can be done particularly quickly because liquid, not gas, is pumped out.

Claims

1. Fitting for a liquid gas bottle comprising a gas tap (2) for gas withdrawal and an opening (3) for refilling a liquid gas bottle, wherein the opening (3) for refilling a liquid gas bottle is connected in a gas-conducting manner to a hose-shaped or tubular line (27) of the fitting, which can extent into a liquid gas bottle by at least 300 mm, preferably at least 400 mm, wherein the gas tap (2) can be opened and closed by a rotary handle (16), and there is an opening (26) at the bottom side of the fitting adjacent to the hose-shaped or tubular line (27), which can be connected to the gas tap in a gas-conducting manner, wherein the hose-shaped or tubular line (27) protrudes relative to the opening (26), characterized in that the opening (3) for refilling the liquid gas bottle is arranged at the upper side of the fitting (1).

2. Fitting according to claim 1, wherein the hose-shaped or tubular line (27) protrudes relative to the opening by at least 200 mm, particularly preferred by at least 300 mm.

3. Fitting according to one of the preceding claims, characterized in that the gas tap (2) protrudes sidewards from the fitting (1).

4. Fitting according to one of the preceding claims, characterized in that the opening (3) for refilling a liquid gas bottle can be opened and closed by a valve.

5. Fitting according to the preceding claim, characterized in that the valve comprises a valve body (6), which is pressed to its closed valve position by a biased spring (8).

6. Fitting according to the preceding claim, characterized in that the valve body (6) is a hollow cylinder, which comprises sideward openings (15).

7. Fitting according to one of the two preceding claims, characterized in that the valve body (6) is provided with a circumferential, exchangeable sealing ring (9), which closes the valve in a liquid and gas tight manner in the closed state.

8. Fitting according to the preceding claim, characterized in that the sealing ring (9) is pressed in the closed state against a conical passage (9), which connects a tubular section (10) with a compared with this broadened tubular section (11).

9. Fitting according to one of the four preceding claims, characterized in that there is a closing element, in particular in the shape of a hollow cylindrical section (29), which, if the valve body (6) is moved in its opened position, interrupts a gas-conducting connection between the gas tap (2) and the opening (26) at the bottom side of the fitting, in which the gas of a connected liquid gas bottle may flow into.

10. Fitting according to the preceding claim, characterized in that the hollow cylindrical section (29) is a section of the line, which connects the gas tap (2) with an opening (26) at the bottom side of the fitting, in which the gas of a connected liquid gas bottle may flow into.

11. Fitting according to one of the preceding claims, characterized in that the gas tap (2) is mandatorily closed when a valve for refilling is opened, and / or vice versa the valve for refilling is mandatorily closed when the gas tap (2) is opened.

12. Fitting according to one of the preceding claims, characterized in that there is a further opening having a quick connector, through which the gas can be withdrawn.

13. Method for refilling a liquid gas bottle with a fitting according to one of the preceding claims in a filling station comprising the steps: • a filling head of the filling station is connected to the opening (3) for refilling, • subsequently, the filling station fills the gas bottle with liquid gas, • subsequent to the filling, the filling station tests leakage of gas from the gas bottle, • if the test reveals that no gas escapes from the gas bottle, the refilled gas bottle is removed from the filling station, • if the test reveals that gas does escape from the gas bottle, the filling station empties the gas bottle by sucking liquid gas through the opening, which is provided for refilling.